BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates to a wiper structure wherein a wiper blade is supported
on a wiper arm in an asymmetrical manner about a connecting point.
[0002] Priority is claimed on Japanese Patent Application No. 2004-196652, filed July 2,
2004, the content of which is incorporated herein by reference.
Background Art
[0003] One type of a wiper apparatus provided on a vehicle, such as an automobile, is a
wiper apparatus in which wiper blade having a plurality of support arms of tournament
structure is supported on a wiper arm, for example. This wiper apparatus is for ensuring
a field of front or rear vision of the vehicle by turning the wiper arm while being
pressed, to thereby wipe the window glass by the blade main body of the wiper blade
(refer to Japanese Unexamined Patent Application, First Publication No. 2003-165422).
[0004] In the above conventional wiper apparatus, because it is necessary to apply the pressing
force evenly on the window glass (windshield), the wiper blade is supported on the
wiper arm in a symmetrical manner about the connecting point, and the spacings of
support points for supporting the blade main body are made as constant as possible.
[0005] Recently, for reasons of vehicle body design, a curved shape has been employed for
the front window glass and the rear window glass. In such a case, the wiping performance
by the wiper blade in a wiper structure that evenly applies the pressing force as
mentioned above, is greatly affected by the shape of the window glass.
[0006] For example, when a window glass having a portion which is greatly curved, is wiped,
the pressing force on the curved portion is increased or decreased compared to the
other portions. Therefore, there is a problem of decreased wiping effect in the vicinity
of the curved portion.
[0007] To address this, it has been considered to use other parts, in order to change the
pressing force locally. However, the wiping performance may be deteriorated as the
weight is increased.
SUMMARY OF THE INVENTION
[0008] Accordingly, it is an object of the present invention to provide a wiper structure
that has a excellent wiping effect even if there is a large curvature portion in a
window glass.
[0009] In order to achieve the above object, a first aspect of the present invention is
a wiper structure for a window glass, including: a wiper arm including a support arm
provided on the wiper arm; and a wiper blade including a blade main body, the wiper
blade being supported on the wiper arm in an asymmetrical manner about a connecting
point, the wiper blade main body being supported at a plurality of support points
on the support arm, wherein a spacing between any two adjacent support points of the
plurality of support points is set wider as a curvature of the window glass increases.
[0010] By such a configuration, the large curvature portion of the window glass corresponds
to the side having a wide spacing with less support points and excellent fittingness,
and due to the elastic force of the blade main body, the curved form of the window
glass can be fitted without being obstructed by the support points.
[0011] A second aspect of the present invention is a tournament-type wiper structure for
a window glass, including: a wiper arm including a support arm provided on the wiper
arm; and a wiper blade including a blade main body, the wiper blade being supported
on the wiper arm in an asymmetrical manner about a connecting point, the wiper blade
main body being supported at a plurality of support points on the support arm, wherein
the number of levels in the tournament is set smaller as a curvature of the window
glass increases.
[0012] By having such a configuration, if the large curvature portion of the window glass
corresponds to the portion for which the number of levels in the tournament of the
wiper blade is lower, and which has a greater depth, a larger bend stroke can be ensured
in the height direction of the blade main body according to the curvature of the window
glass, so that the large curvature portion can be fitted.
[0013] A third aspect of the present invention is a tournament-type wiper structure for
a window glass, including: a wiper arm including a support arm provided on the wiper
arm; and a wiper blade including a blade main body, the wiper blade being supported
on the wiper arm in an asymmetrical manner about a connecting point, the wiper blade
main body being supported at a plurality of support points on the support arm, wherein
the number of levels in the tournament is set smaller as a curvature of the window
glass increases, and a spacing between any two adjacent support points of the plurality
of support points is set wider for the large curvature portion of the window glass.
[0014] By having such a configuration, if the large curvature portion of the window glass
corresponds to the portion for which the number of levels in the tournament of the
wiper blade is lower, and which has a greater depth, a larger bend stroke can be ensured
in the height direction of the blade main body according to the curvature of the window
glass, so that the large curvature portion can be fitted. Furthermore, if the large
curvature portion of the window glass corresponds to the side having a wide spacing
with less support points and excellent fittingness, then due to the elastic force
of the blade main body, the curved form of the window glass can be fitted without
being obstructed by the support points.
[0015] According to a fourth aspect of the present invention, in the wiper blade described
above, the wiper blade is set such that a length from the connecting point is shorter
on a side having a greater curvature of the window glass.
[0016] By having such a configuration, the pressing force per a unit length on the large
curvature portion of the window glass can be increased.
[0017] According to the first aspect of the present invention, the large curvature portion
of the window glass corresponds to the side having a wide spacing with less support
points and excellent fittingness, and due to the elastic force of the blade main body,
the curved form of the window glass can be fitted without being obstructed by the
support points. Therefore, even in a portion having a partially large curvature, this
curvature can be fitted, so that there is an effect of being able to increase the
wiping effect. Moreover, since no special member is required for changing the pressing
force of the wiper blade to match with the curved form, the wiper apparatus can be
lightened.
[0018] According to the second aspect of the present invention, if the large curvature portion
of the window glass corresponds to the portion for which the number of levels in the
tournament of the wiper blade is lower, and which has a greater depth, a larger bend
stroke can be ensured in the height direction of the blade main body according to
the curvature of the window glass, so that the large curvature portion can be fitted.
Therefore, even in a portion having a partially large curvature, the blade main body
can increase the bent stroke and follow with enough margin, so that there is the effect
of being able to increase the wiping effect. Moreover, since no special member is
required for changing the pressing force of the wiper blade, the wiper apparatus can
be lightened.
[0019] According to the third aspect of the present invention, if the large curvature portion
of the window glass corresponds to the portion for which the number of levels in the
tournament of the wiper blade is lower, and has a greater depth, a larger bend stroke
can be ensured in the height direction of the blade main body according to the curvature
of the window glass, so that the large curvature portion can be fitted. Furthermore,
if the large curvature portion of the window glass corresponds to the side having
a wide spacing with less support points and an excellent fittingness, then due to
the elastic force of the blade main body, the curved form of the window glass can
be fitted without being obstructed by the support points. Therefore, even in a portion
having a partially large curvature, there is an effect of being able to further increase
the wiping effect. Moreover, since no special member is required for changing the
pressing force of the wiper blade, the wiper apparatus can be lightened.
[0020] According to the fourth aspect of the present invention, the pressing force per a
unit length on the large curvature portion of the window glass can be increased. Hence,
there is an effect of being able to reliably wipe without leaving a trace.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021]
FIG. 1 is a partial perspective view of a tailgate furnished with a wiper structure
of an embodiment of the present invention.
FIG. 2 is an assembled perspective view of a wiper apparatus of the embodiment of
the present invention.
FIG. 3 is an exploded perspective view of the wind wiper apparatus shown in FIG. 2.
FIG. 4 is a cross-sectional view taken along the line A-A of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Hereunder is a description of an embodiment of the present invention, with reference
to drawings.
[0023] As shown in FIG. 1, a wiper apparatus 3 which wipes a rear window glass 2 is provided
on a tailgate 1 that is the back door of a vehicle. The wiper apparatus 3 is linked
to a pivot shaft 4 which is rotated by a drive unit (not shown). This pivot shaft
4 is provided in the vicinity of the lower side of a glass installation opening 5
of the tailgate 1.
[0024] As shown in FIG. 2 and FIG. 3, an arm base 6 is attached to the pivot shaft 4, and
a shank 8 having a U-shaped cross-sectional is elastically supported on the arm base
6 via a hinge 7 so as to be able to stand up. An arm piece 9 with the tip thereof
bent to the left as shown in FIG. 1, is fixed to a tip portion of the shank 8, and
a wiper blade 10 is swingably supported on the tip of the arm piece 9. The arm base
6, the shank 8, and the arm piece 9 constitute a wiper arm 11 of the wiper apparatus
3.
[0025] A tournament-type wiper blade 10 is detachably attached to the tip of the arm piece
9. Specifically, the wiper blade 10 includes a primary arm 12 which is latched to
a U-shaped portion 13 at the tip of the arm piece 9. A latch 14 is swingably supported
on the approximate central portion of the primary arm 12 so that the U-shaped portion
13 at the tip of the arm piece 9 can be fastened to this latch 14. The support portion
of the primary arm 12 and the latch 14 constitutes a connecting point R.
[0026] Here, the primary arm 12 is set such that, centered on the connecting point R, the
wiper arm 11 base side length of the primary arm 12 is shorter than the tip side length.
Moreover, a first secondary arm (support arm) 15 is swingably supported on the wiper
arm 11 base end of the primary arm 12 by a pin 16, and a second secondary arm (support
arm) 17 is swingably supported on the wiper arm 11 tip end by another pin 16. Furthermore,
claws (support points) 19 which slidably support a blade main body 18, are provided
on the opposite ends of the first secondary arm 15.
[0027] On the other hand, a yoke support portion 20 is formed on the wiper arm 11 tip end
of the second secondary arm 17, and a yoke (support arm) 21 is swingably supported
thereon by another pin 16. Claws (support points) 22 which slidably support the blade
main body 18 are provided on the opposite ends of the yoke 21. A claw (support point)
23 which slidably supports the blade main body 18 is provided on the wiper arm 11
base end of the second secondary arm 17.
[0028] Furthermore, the blade main body 18 is slidably supported on the two claws 19 on
the opposite ends of the first secondary arm 15, the claw 23 on the wiper arm 11 base
end of the second secondary arm 17, and the two claws 22 of the yoke 21. Here, one
end of the blade main body 18 is fastened to and restrained by either one of the claw
22 on the outer end of the yoke 21 and the claw 19 on the wiper arm 11 base end of
the first secondary arm 15, so that when the blade main body 18 is bent and deformed
at the time of wiping by the wiper apparatus 3, it can relatively slide on the portion
of the plurality of non-restraining claws by using a margin maintained at the unrestrained
end.
[0029] As shown in FIG. 1, the rear window glass 2 is formed so that, at a point which is
slightly lower than the center in the vertical direction, the vertical curvature increases
across the vehicle widthwise direction, and the lower portion is curved sharply downward.
The wiper arm 11 moves to wipe so as to transverse this large curvature portion W,
and the length of the wiper arm 11 is set so that the large curvature portion W of
the rear window glass 2 is positioned between the claws 19 of the first secondary
arm 15. Moreover, the wiper blade 10 is supported in an asymmetrical manner about
the connecting point R, with the length from the connecting point R to the respective
ends set such that the length (length I) to the end on the side corresponding to the
large curvature portion W of the rear window glass 2 is shorter than the length (length
L) on the side corresponding to the small curvature portion of the rear window glass
2 (L>I).
[0030] Furthermore, assuming that the spacing between the respective claws 19 of the first
secondary arm 15 is A, the spacing between the respective claws 22 of the yoke 21
is B, the spacing between the claw 22 on the wiper arm 11 base side of the yoke 21
and the claw 23 of the second secondary arm 17 is C, and the spacing between the claw
23 of the second secondary arm 17 and the claw 19 on the wiper arm 11 tip side of
the first secondary arm 15 is D, the spacing A between the respective claws 19 of
the first secondary arm 15 is set so as to be the greatest corresponding to the magnitude
of the curvature of the rear window glass 2 (A>B, C, D).
[0031] Here, the reason why the spacing between the respective claws is set corresponding
to the curvature of the rear window glass 2 is that when the curvature of the rear
window glass 2 is large, then in order to bend the blade main body 18 for that large
amount, it is necessary to make the spacing between the respective claws as large
as possible so that the blade main body 18 can be bent with enough margin.
[0032] Moreover, in order to bend the blade main body 18 in such a manner, a space for bending
the blade main body 18 is required. In this embodiment, the spacing A between the
respective claws 19 of the first secondary arm 15 is set so as to be greater than
for the other spacings, so that the blade main body 18 can be readily bent. Moreover,
enough bend space X for the blade main body 18 is ensured in the height direction
of the wiper blade 10, between the claws 19 of the first secondary arm 15 for which
the number of levels in the tournament without the yoke 21 is low. That is, the first
secondary arm 15 has a deeper space than the yoke 21, and hence the bend space of
the blade main body 18 can be kept larger.
[0033] As shown by chain lines in FIG. 2 and FIG. 3, a cover member 24 which covers the
exterior of the tip side of the wiper blade 10 is provided on the wiper arm 11.
[0034] Next is a description of the operation of the wiper structure of the present invention.
[0035] As shown in FIG. 1, when the wiper arm 11 is turned back and forth from the lower
position LOW to the higher position HI to wipe the rear window glass 2, the blade
main body 18 can wipe the rear window glass 2 so that it moves in parallel with this
large curvature portion W until it reaches the large curvature portion W of the rear
window glass 2. However, once it starts to pass through the large curvature portion
W, although this large curvature portion W is not curved enough to bend the blade
main body 18 at the beginning of passing, the blade main body 18 is gradually turned
to a direction crossing over the large curvature portion W and it is gradually bent.
[0036] However, as shown in FIG. 4, even if the wiper blade 10 reaches the position MID
which crosses over the large curvature portion W at right angles, the blade main body
18 which is sufficiently bent with enough margin between the claws 19 of the first
secondary arm 15 can touch on the large curvature portion W, so that wiping can be
performed with no trace left. At this time, the blade main body 18 can wipe the large
curvature portion W of the rear window glass 2 by corresponding to the spacing between
the claws 19 of the first secondary arm 15 for which the number of levels in the tournament
is smaller and has a greater depth than the yoke 21. Accordingly, enough bend space
X is also ensured in the height direction of the blade main body 18, so that the blade
main body 18 can be smoothly bent.
[0037] Additionally, the pressing force on the wiper blade 10 is distributed about the connecting
point R. However, the wiper blade 10 is set as a whole such that the length from the
connecting point R on the side corresponding to the large curvature portion W of the
rear window glass 2 is shorter than the length on the side corresponding to the small
curvature portion. Therefore, the pressing force on the large curvature portion W
per a unit length is increased accordingly, so that the large curvature portion W
of the rear window glass 2 can be wiped with no trace left.
[0038] According to the above embodiment, the large curvature portion W of the rear window
glass 2 corresponds to the first secondary arm 15 including the claws 19 having a
wide spacing with less support points and an excellent fittingness, and due to the
elastic force of the blade main body 18, the curved form of the rear window glass
2 can be touched without being adversely affected by the claws 19. Therefore, the
wiping effect can be increased even in the large curvature portion W of the rear window
glass 2 where traces tend to be left. Moreover, since no extra member is required
for changing the pressing force of the wiper blade 10, it is possible to reduce the
weight of the wiper apparatus 3.
[0039] Furthermore, the spacing between the respective claws 19 of the first secondary arm
15 for which the number of levels in the tournament of the wiper blade 10 is lower,
and which has a greater depth, can be made to correspond to the large curvature portion
W of the rear window glass 2, and a larger bend space X can be ensured in the height
direction of the blade main body 18 compared to the portion supported by the yoke
21, so that the large curvature portion W can be toutched. Therefore, the present
invention is advantageous in that even in the large curvature portion W of the rear
window glass 2, the wiping effect where the blade main body 10 is largely bent with
enough margin and touchs the window glass, can be increased.
[0040] Furthermore, in this embodiment, the wide spacing region between the claws 19 of
the first secondary arm 15, is set corresponding to rear window glass 2 so as to span
over the large curvature portion W. Therefore, this, together with ensuring the bend
space X as mentioned above, enhances the wiping effect even in the large curvature
portion W with no trace left.
[0041] The present invention is not limited to the above embodiment. The tournament structure
of the abovementioned structure is an example and is not to be considered as limiting.
Moreover, although the rear window glass 2 was described as an example, the present
invention can be applied to a wiper apparatus for a front window glass.
[0042] In the above, a preferred embodiment has been described, however the present invention
is not limited to this embodiment. Additions, omission, substitutions of the construction,
and other modifications can be made without departing from the spirit or scope of
the present invention. Accordingly, the invention is not to be considered as being
limited by the forgoing description, and is only limited by the scope of the appended
claims.
[0043] A wiper structure for a window glass, includes a wiper arm (11) comprising a support
arm provided on the wiper arm (11); and a wiper blade (10) comprising a blade main
body, the wiper blade (10) being supported on the wiper arm (11) in an asymmetrical
manner about a connecting point (R), the wiper blade main body (18) being supported
at a plurality of support points on the support arm, wherein a spacing between any
two adjacent support points of the plurality of support points is set wider as a curvature
of the window glass increases.
1. A wiper structure for a window glass, comprising:
a wiper arm (11) comprising a support arm provided on the wiper arm (11); and
a wiper blade (10) comprising a blade main body, the wiper blade (10) being supported
on the wiper arm (11) in an asymmetrical manner about a connecting point (R), the
wiper blade main body (18) being supported at a plurality of support points on the
support arm,
wherein a spacing between any two adjacent support points of the plurality of support
points is set wider as a curvature of the window glass increases.
2. A wiper structure according to claim 1, wherein the wiper blade (10) is set such that
a length from the connecting point (R) is shorter on a side having a greater curvature
of the window glass.
3. A tournament-type wiper structure for a window glass, comprising:
a wiper arm (11) comprising a support arm provided on the wiper arm (11); and
a wiper blade (10) comprising a blade main body, the wiper blade (10) being supported
on the wiper arm (11) in an asymmetrical manner about a connecting point (R), the
wiper blade main body (18) being supported at a plurality of support points on the
support arm,
wherein the number of levels in the tournament is set smaller as a curvature of the
window glass increases.
4. A wiper structure according to claim 3, wherein the wiper blade (10) is set such that
a length from the connecting point (R) is shorter on a side having a greater curvature
of the window glass.
5. A tournament-type wiper structure for a window glass, comprising:
a wiper arm (11) comprising a support arm provided on the wiper arm (11); and
a wiper blade (10) comprising a blade main body, the wiper blade (10) being supported
on the wiper arm (11) in an asymmetrical manner about a connecting point (R), the
wiper blade main body (18) being supported at a plurality of support points on the
support arm,
wherein the number of levels in the tournament is set smaller as a curvature of the
window glass increases, and a spacing between any two adjacent support points of the
plurality of support points is set wider for the large curvature portion of the window
glass.
6. A wiper structure according to claim 5, wherein the wiper blade (10) is set such that
a length from the connecting point (R) is shorter on a side having a greater curvature
of the window glass.